TeXes Science Practice Test

Which macromolecules are defined as polymers made of repeating monomers?

1. Carbohydrates and lipids

2. Proteins and nucleic acids

3. Carbohydrates, proteins, and nucleic acids

4. Only carbohydrates

The correct answer is: Carbohydrates, proteins, and nucleic acids

The correct response highlights that carbohydrates, proteins, and nucleic acids are all categorized as macromolecules that consist of polymers formed by repeating units known as monomers. Carbohydrates are constructed from simple sugars (monosaccharides) that bond together to form polysaccharides. Examples include starch and cellulose, which are long chains of sugar monomers. Proteins are made of amino acids linked together through peptide bonds, forming polypeptide chains. These chains fold into complex three-dimensional structures, functioning in various biological roles. Nucleic acids, such as DNA and RNA, are assembled from nucleotide monomers. Each nucleotide contains a sugar, a phosphate group, and a nitrogenous base, and when linked together, they form long chains that encode genetic information. In contrast, lipids do not fall under the category of polymers made from repeating monomers, as they are typically composed of glycerol and fatty acids and do not form long-chain structures like the other three macromolecule types. Therefore, the inclusion of carbohydrates, proteins, and nucleic acids as polymeric structures justifies the correctness of the provided answer.